This disclosure relates to power supply systems for computers, and more particularly to battery backup systems.
Computers that are plugged into an AC power outlet to supply power to the computer typically include a power supply unit that converts input AC power to DC power. The DC power produced by the power supply is used to drive the various components of the computer. For example, the ATX power supply described in the ATX Specification published by Intel Corporation, February 1997, is used to supply power to certain computers.
When adequate AC power is not supplied to the power supply unit, the operation of the computer may cease. This, in turn, may lead to data loss and/or damage to components of the computer.
Adequate power may not be supplied to the power supply, for example, due to a power interruption or brown out condition. An uninterruptible power supply (xe2x80x9cUPSxe2x80x9d) may be attached to the computer in order to supply AC power to the power supply unit in the event AC power is not available from the AC power outlet. A conventional UPS unit is typically configured as a standalone unit that must be installed and maintained separately from the computer with which it is used. A conventional UPS unit typically includes a battery for providing power to the computer in the event of a power interruption or brown out condition. Such a conventional UPS unit typically includes power conversion circuitry to convert the DC power provided by the battery to the AC power input to the computer""s power supply unit.
UPS units also typically include some mechanism for sending a message to the computer indicating that a power interruption or brown out condition has occurred. Such a message can be sent using a network interface card, serial port, or universal serial bus (xe2x80x9cUSBxe2x80x9d) port that connects the UPS unit to a computer and/or a computer network. The connected computer can be configured to initiate a controlled shutdown in response to receiving such a message.